1. Field of the Invention
The present invention relates to polyolefinic foam particles which have been provided with additives during their production in a dispersion process, and a process for their production as well as moldings produced from such foam particles.
2. Discussion of the Background
The production of polyolefinic particle foams by the dispersion process is conventional and is described in many patent applications, for example EP-A-0 053 333 and EP-A-0 095 109. Particle foams produced in this way can be processed into moldings by known methods.
Owing to their property profile, polyolefinic particle foams or the moldings produced therefrom have many applications. However, for certain fields of application, the properties of the particle foam have to be modified. For example, flame retardant treatment is frequently demanded in the building sector, while the electrical industry often requires an antistatic treatment. In other cases, the market desires a colored product.
Processes for the treatment of particle foams are known. In these processes, the particle foam is customarily provided with the desired treatment by subsequent coating (DE-A 42 35 693). However, this generally represents an additional processing step for the processor. In addition, it is frequently observed that the active component is rubbed off the molding, and the cooling water may be contaminated during processing. In addition, intensive steaming is required for good welding of the foam beads.
Thus, there remains a need for polyolefinic particle foams which are free of such drawbacks. There also remains a need for a process for preparing such polyolefinic foams which is free of the above-mentioned drawbacks.